The treatment of disease such as vascular disease by local pharmacotherapy presents a means of delivering therapeutic drug doses to target tissues while minimizing systemic side effects. Such localized delivery of therapeutic agents has been proposed or achieved using medical devices such as catheters, needle devices and various coated implantable devices such as stents.
The localized delivery of therapeutic agents using needle devices has the advantages of precise placement and accurate control over the volume and rate of delivery. However, delivery using needle devices creates a needle track, which allows leakage or outflow of the therapeutic agent. Additionally, the nature of the tissue may allow for dispersion away from the injection site, which may not be desired.